The present invention relates to checkstands, and, more specifically, to store checkstands.
A checkstand is a station at which a customer or clerk unloads the items the customer intends to purchase, e.g., groceries, a register clerk scans or enters the prices of the items, the customer pays for the items, the items are bagged, and the bagged groceries are placed in a cart or handed to the customer. In some stores, a separate clerk bags the items and places the bags into a cart. A number of checkstands are usually lined along the exit of a store so that multiple customers can purchase items at the same time on the way out of the store.
One design of a checkstand includes a front module upon which the customer unloads groceries or other items. A scanner and register are located at the trailing end of the front module. The front module usually includes a conveyor, called an xe2x80x9caccumulation conveyor,xe2x80x9d for conveying the groceries toward the scanner and the cash register. A register clerk lifts each of the items from the accumulation conveyor and either scans the item across the scanner, or manually enters the price and stock number information in the cash register. The scanned items are placed on a second conveyor, called a xe2x80x9ctake-away conveyor,xe2x80x9d that extends to a rear module. The take-away conveyor deposits the scanned items at the trailing end of the rear module, where a bagging clerk places each of the scanned items into bags.
In normal operation of a checkstand, such as is described above, the leading edge of the take-away conveyor extends from the trailing edge of the scanner to the rear of the rear module, such that a constant surface is formed between the accumulation conveyor, the scanner, and the take-away conveyor. This arrangement is convenient for the register clerk, allowing him or her to quickly scan-and-pass a large amount of items. For ease of description, the configuration and operation in which the take-away conveyor extends from the trailing edge of the scanner will be called xe2x80x9cscan-and-pass.xe2x80x9d
A large number of grocery stores are reducing their work force by eliminating the need for a separate bagging clerk during slower periods of business or at checkstands where a limited number of items are purchased. When a separate bagging clerk is not used, the register clerk both scans and bags the groceries. For maximal efficiency, it is desirable for the register clerk to bag the groceries as they are scanned. To provide this service, some prior art checkstands include a take-away conveyor having a leading end which is movable away from the trailing end of the scanner. Withdrawal of the take-away conveyor exposes an area located beneath the leading end of the conveyor. The exposed area includes a support shelf for use in bagging groceries and other items. If the take-away conveyor is partially withdrawn, a single bag can be inserted between the leading end of the take-away conveyor and the trailing end of the scanner. This single bag may be located, for example, on a bag stand. In this arrangement of the checkstand, the register clerk may scan an item and reach over the bag stand and place the item on the take-away conveyor, or may place the scanned item in a bag on the bag stand. For ease of description, the configuration and operation in which the take-away conveyor is in this intermediate position will be called xe2x80x9cscan-and-bag.xe2x80x9d
For some prior art checkstands, the take-away conveyor is designed to be further retracted (i.e., away from the bag stand) to provide access to a pass-through, adjacent to the bag stand, via which the register clerk may access the customer""s cart to load bags that have been filled at the bag stand. For ease of description, the configuration and operation in which the take-away conveyor is retracted so that the register clerk may pass will be called xe2x80x9cwalk-through.xe2x80x9d
The prior art provides at least three ways of withdrawing the take-away conveyor from the trailing edge of the scanner. In a first checkstand design, the take-away conveyor is of fixed length, and is mounted so it can slide into a recess in the rear module. The register clerk pulls the take-away conveyor forward to the scanner to perform scan-and-pass operation, and pushes the take-away conveyor backward into the recess to perform the scan-and-bag or the walk-through operations.
There are a number of problems with a manually-operated retractable, take-away conveyor. First, the manually-operated retractable conveyor is often heavy and difficult to move in or out of the rear module. Thus, the register clerk may not take advantage of the reconfigurable aspects of the checkstand. In addition, in the scan-and-pass position, the trailing end of the take-away conveyor is removed from the trailing end of the rear module, leaving a large portion of the rear module recess exposed. Typically, a cover plate extends over a portion of the recess to minimize the exposed area. Items moving along the take-away conveyor when it is in the scan-and-pass position are deposited onto the leading edge of the cover plate. This leading edge is removed from the back end of the rear module by a length that is at least as long as the slide of the take-away conveyor. To reach the groceries or other items conveyed by the take-away conveyor, a bagging clerk must extend out over the cover plate. Constant reaching and extension by the bagging clerk is inconvenient, and may be uncomfortable for the bagging clerk. Another downside of the manually-operated retractable take-away conveyors is that the conveyor recess, and therefore the conveyor length, is limited by the length of the rear module recess.
Another checkstand design utilizes a fold down take-away conveyor that extends between the rear module and the scanner. An example of such a checkstand is shown in U.S. Pat. No. 4,182,433 to Foster. In scan-and-pass operation, the fold down conveyor extends horizontally from the trailing edge of the scanner to the leading edge of the rear module. A second take-away conveyor extends along the top surface of the rear module and abuts the trailing edge of the fold down conveyor. After being scanned, items are placed on the fold down conveyor, and are conveyed along the fold down conveyor to the second take-away conveyor. The groceries then move along the second take-away conveyor toward the trailing end of the rear module. If the register clerk wishes to perform a scan-and-bag or walk-through operation, the leading end (closest to the scanner) of the fold down conveyor is released, and the conveyor is rotated downward about the trailing end (closest to the rear module) of the conveyor so that the fold down conveyor extends perpendicularly to the floor. A single bag is then inserted adjacent to the trailing end of the scanner, and the register clerk is provided a station which permits convenient scanning and bagging of groceries. When the single bag is removed from the second take-away conveyor, a walk-through space is provided. Because the fold down conveyor has only two configurations, the scan-and-bag configuration described above cannot be easily provided. In addition, manipulation of the fold down conveyor and bagging stand are difficult and time consuming. This hindrance may cause a register clerk not to use the different configurations provided by the checkstand.
The assignee of the present invention solved the above-described problems by developing a checkstand having a telescoping take-away conveyor. The telescoping take-away conveyor is the subject of the commonly assigned U.S. Pat. Nos. 5,755,308 and 6,035,971. Each of these patents is directed to a checkstand having a telescoping take-away conveyor that is reconfigurable between the scan-and-pass, walk-through, and scan-and-bag positions described above. The telescoping take-away conveyor in one embodiment provides automatic retraction and extension of the telescoping take-away conveyor between the scan-and-pass, scan-and-bag, and walk-through positions. A friction roller in the telescoping take-away conveyor causes the telescoping take-away conveyor to have a tendency to either retract or expand, depending upon the direction of rotation of the conveyor belt for the telescoping take-away conveyor.
The telescoping take-away conveyor offers many advantages over prior art checkstands. For the telescoping take-away conveyor that automatically retracts and extends, a register clerk does not have to manually lift or slide the telescoping take-away conveyor, nor leave his or her post to reconfigure the checkstand. In addition, the telescoping take-away conveyor expands, or lengthens, to extend to the front module (i.e., in scan-and-pass mode), yet maintains a back end of the conveying surface at the back of the rear module. In this manner, items placed on the telescoping take-away conveyor while the telescoping take-away conveyor is in the scan-and-pass configuration are deposited on the rear portion of the rear module, instead of an intermediate position.
Although the telescoping take-away conveyor works well for its intended purpose, the specific operation described in the above patents for switching between the scan-and-pass, walk-through, and scan-and-bag positions involves using two buttons at correct times. The first button determines the rotation direction of the telescoping take-away conveyor, which in turn determines whether the telescoping take-away conveyor attempts to expand or retract. The second button operates a solenoid that causes a mechanical stop to move back and forth so that, in a first position of the mechanical stop, the telescoping take-away conveyor stops retraction from the scan-and-bag position at the walk-through position, and at a second position of the mechanical stop, the telescoping take-away conveyor retracts past the scan-and-bag position to the walk-through position. While this operation is basically simple, it still requires some training to learn the operation of the two buttons, and may be difficult for some clerks to grasp. Moreover, the use of the solenoid in the extension/retraction mechanism adds expense to the manufacture of the checkstand.
The present invention is directed to an improved extension/retraction mechanism for a telescoping conveyor used, for example, as a take-away conveyor in a checkstand. The extension/retraction mechanism is a mechanism that is configured to selectively stop and hold the telescoping take-away conveyor at the scan-and-bag position as the telescoping take-away conveyor is moving between the walk-through and scan-and-pass positions.
In accordance with one aspect of the present invention, the extension/retraction mechanism includes a cam follower that moves along with the telescoping take-away conveyor and that is pivotally attached to the telescoping take-away conveyor. The cam follower rides within a cam track as the telescoping conveyor moves between the scan-and-bag, walk-through, and scan-and-pass positions. The cam track includes a series of turn surfaces so that the cam follower may change course (e.g., along a different pathway or direction within the cam track) as the telescoping take-away conveyor moves along the cam track. The cam track also includes at least one pocket for retaining the cam follower when the telescoping take-away conveyor is in the scan-and-bag position.
The cam track preferably includes a first pathway along which the cam follower travels as the telescoping take-away conveyor is advanced forward from the walk-through position. A first turn surface is located at a forward end of the first pathway, and is engaged just prior to the telescoping take-away conveyor reaching a location adjacent to the scan-and-bag position. The turn surface causes the cam follower to turn off the first pathway.
If the telescoping take-away conveyor is to stop at the intermediate, scan-and-bag position, the telescoping take-away conveyor is stopped while it advances along the first turn surface (e.g., by contacting a bag stand that is inserted behind the scanner). The telescoping take-away conveyor is then retracted. The movement of the cam follower along the first turn surface causes the cam follower to no longer be aligned with the first pathway. A pocket is located rearward of the first turn surface, and receives the cam follower as the telescoping take-away conveyor is retracted. The engagement of the cam follower with the pocket prevents further retraction. Thus, the telescoping take-away conveyor is held in the scan-and-bag position.
To remove the telescoping take-away conveyor from the scan-and-bag position, the telescoping take-away conveyor is extended, causing the cam follower to be removed from the pocket. The cam follower then engages a second turn surface, which directs the cam follower to a second pathway. The telescoping take-away conveyor may then move forward along the second pathway to the scan-and-pass position, or may be returned along the second pathway to the walk-through position. Upon returning to the walk-through position, the second pathway preferably returns the cam follower to the first pathway, e.g., along a curved turn surface. Thus, upon advancing the telescoping take-away conveyor again, the cam follower travels along the first pathway again.
The first turn surface, the first pathway, and the second pathway are preferably arranged such that, when the cam follower runs along the first turn surface, and the telescoping take-away conveyor extends beyond the scan-and-bag position, the cam follower is fed by the first turn surface into the second pathway. The cam follower may continue up the second pathway until the telescoping take-away conveyor reaches the scan-and-pass position. To return to the walk-through position, the telescoping take-away conveyor may be retracted, whereby the cam follower returns to the first pathway via the second pathway.
The extension/retraction mechanism of the present invention provides a means by which the telescoping take-away conveyor may alternatively stop at the scan-and-bag or scan-and-pass locations without requiring a solenoid or other complicated or expensive parts. The extension/retraction mechanism further provides a mechanism whereby a telescoping take-away conveyor may be retracted and extended between the walk-through, scan-and-pass, and scan-and-bag positions by using a two switches or buttons. For example, the telescoping take-away conveyor may include a friction roller or other friction device whereby changing the direction of rotation of the conveyor belt for the telescoping take-away conveyor causes the telescoping take-away conveyor to have a tendency to either retract or expand. Using such a device, a clerk may move the telescoping take-away conveyor between the walk-through, scan-and-pass, and scan-and-bag positions by simply reversing the direction of rotation of the telescoping take-away conveyor.
Other advantages will become apparent from the following detailed description when taken in conjunction with the drawings, in which: